The value of admission and pre-discharge serum c-reactive protein levels and its ratio in predicting ischemic events among low risk post myocardial infarction patients.

Inflammation has been thought to play a role in the atherosclerotic process. C-reactive protein is the objective index of the overall inflammatory activity in the body
OBJECTIVES: This study evaluates the prognostic values of the admission, pre-discharge, and the ratio of pre-discharge over admission levels of C-reactive protein among patients with uncomplicated acute myocardial infarction and normal left ventricular function
METHODS AND RESULTS: Venous blood samples for C-reactive protein were obtained on admission and before discharge on 61 patients (44 males, 17 females) with a diagnosis of acute myocardial infarction who had an LV ejection fraction 45 percent and showed no signs of ischemia on pre-discharge exercise stress test. Follow-up for cardiac events was done for a period of six months. Baseline characteristics were essentially the same between groups with and without cardiac events except for the ejection fraction (p=0.001)
Serum C-reactive protein levels of patients on admission, pre-discharge and ratio of predischarge over admission were significantly higher for patients with cardiac events compared to patients without cardiac events. When the ratios of pre-discharge over admission serum CRP were divided into quartiles, patients belonging to the fourth quartile (ratio 0.7620) were found to have a 15-fold increased probability of developing a cardiac event p=0.001, RR 15.33, Cl 5.13-45.79) compared to patients in the first quartiles. Multivariate analysis revealed that the ratio of pre-discharge over admission CRP of greater than 0.6 is the only independent predictor of cardiac events and has a sensitivity of 100 percent and specificity of 97.7 percent for predicting cardiac events during the follow-up period
CONCLUSION: The ratio of pre-discharge over admission levels of serum C-reactive protein is more sensitive and specific than the admission or pre-discharge levels of C-reactive protein in predicting cardiac events during follow up period of low-risk post-myocardial infarction patients. Acute phase response to inflammatory events such as acute myocardial may vary according to undetermined individual determinants which in this case might be genetics. (Author)